Switch Smilie Parsing On/Off for one Post

Hmm, only 3 Stars, maybe I should explain the feature a little bit more:

For example, when you write :) WP will make an image instead of this 2 letters. But maybe, there is a situation and you don't want to display this image instead of the 2 letters, then you will need a switch, to turn the parsing off.

I know, there is a global switch to turn the parsing on/off, but this is to inflexible.